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1.
Climate impacts on coastal and estuarine systems take many forms and are dependent on the local conditions, including those set by humans. We use a biocomplexity framework to provide a perspective of the consequences of climate change for coastal wetland ecogeomorphology. We concentrate on three dimensions of climate change affects on ecogeomorphology: sea level rise, changes in storm frequency and intensity, and changes in freshwater, sediment, and nutrient inputs. While sea level rise, storms, sedimentation, and changing freshwater input can directly impact coastal and estuarine wetlands, biological processes can modify these physical impacts. Geomorphological changes to coastal and estuarine ecosystems can induce complex outcomes for the biota that are not themselves intuitively obvious because they are mediated by networks of biological interactions. Human impacts on wetlands occur at all scales. At the global scale, humans are altering climate at rapid rates compared to the historical and recent geological record. Climate change can disrupt ecological systems if it occurs at characteristic time scales shorter than ecological system response and causes alterations in ecological function that foster changes in structure or alter functional interactions. Many coastal wetlands can adjust to predicted climate change, but human impacts, in combination with climate change, will significantly affect coastal wetland ecosystems. Management for climate change must strike a balance between that which allows pulsing of materials and energy to the ecosystems and promotes ecosystem goods and services, while protecting human structures and activities. Science-based management depends on a multi-scale understanding of these biocomplex wetland systems. Causation is often associated with multiple factors, considerable variability, feedbacks, and interferences. The impacts of climate change can be detected through monitoring and assessment of historical or geological records. Attribution can be inferred through these in conjunction with experimentation and modeling. A significant challenge to allow wise management of coastal wetlands is to develop observing systems that act at appropriate scales to detect global climate change and its effects in the context of the various local and smaller scale effects.  相似文献   

2.
This paper introduces the Special Issue of the Proceedings of the Geologists' Association on ‘Valuing the Quaternary – Nature Conservation and Geoheritage’, arising from the International Union for Quaternary Research (INQUA) Congress in Dublin, in July 2019. It presents an overview of the values of Quaternary geoheritage, which merit recognition as an integral part of nature conservation, to protect priority sites and features for scientific research and education, and to deliver wider ecological, cultural and aesthetic benefits. The paper highlights the benefits of incorporating knowledge and understanding of Quaternary geoheritage for nature conservation and society. Palaeoenvironmental, palaeoecological and palaeobiological archives are a key source of ecological and environmental data that allow learning from the past to help address contemporary conservation challenges such as biodiversity loss, anthropogenic pressures and climate change. Quaternary science plays a vital part in supporting the wider nature conservation agenda, including strengthening the role of protected and conserved areas in the sustainable management of natural capital and ecosystem services, climate change adaptation, marine conservation, nature restoration and recovery, connecting people and nature and informing nature-based solutions to threats faced by society. However, challenges remain to achieve protection of key geoheritage sites and landscapes globally, and to integrate better understanding of geodiversity in nature conservation research, policy development and practice to help address the twin crises facing nature conservation – biodiversity loss and climate change. Quaternary studies provide temporal and spatial perspectives to inform forward-looking nature conservation that is dynamic rather than static in outlook.  相似文献   

3.
The Yalgorup Plain of southwestern Australia is underlain by two limestone formations and a linear quartz-sand formation containing limestone lenses. These limestones record carbonate deposition in seagrass banks during the Pleistocene; they are capped either by a prograding beach-ridge system of small cuspate forelands or a quartz-rich shore-parallel coastal barrier. The cuspate forelands formed behind protective offshore limestone reefs within a given Pleistocene wind-and-wave field, while the quartz-rich coastal dune barrier formed under enhanced swell conditions. These formations record three different Pleistocene interglacial depositional events, separated by unconformities, each linked to a distinct climate and mean sea level. Foraminiferal assemblages within the two limestones and within the limestone lenses of the quartz-sand formation faithfully record changes in minimum seawater temperature, reflecting these changes in climate. They indicate a cycle of warm–cool–warm water accumulation of carbonates. Such a record of both climate and sea level history for southwestern Australia is unique, contributing greatly to the Pleistocene coastal sedimentary history of limestones within southwestern Australia. These formations occur within the globally unique setting of Western Australia and are conserved within a National Park and represent an outstanding record of Quaternary coastal geomorphic development in terms of both carbonate and siliciclastic sedimentation linked to both climate and sea level changes. Given their array of lithofacies, environmental setting, sea level and climate changes, as well as their biostratigraphy reflecting these changes, these formations form a sedimentary ‘package’ that is of global geoheritage significance, with many of its inherent geological features also of global to national geoheritage significance.  相似文献   

4.
Ferreira  Óscar  Kupfer  Sunna  Costas  Susana 《Natural Hazards》2021,109(3):2221-2239

Overwash is one of the most prominent hazards affecting coastal zones, and the associated consequences are expected to increase because of both sea-level rise and intensification of coastal occupation. This study used a 23-year data set of wave heights and tide-surge levels to define return periods of overwash potential for current and future sea-level conditions, namely 2055 and 2100, at two sites from South Portugal. A relevant intensification of both frequency and magnitude of the overwash is expected to occur by mid-century if adaptation measures are not taken and further aggravated by 2100. Current overwash levels with a return period of 100-years can reach a return period lower than 20-years by 2055 and 10-years by 2100. However, these values are rather variable from site to site, highlighting the urgency to develop detailed local studies to identify climate change impacts along coastal sectors, based on validated equations and long-term time series. These could be easily carried by replicating and adapting the here proposed methodology to sandy coasts worldwide. Understating the impact that climate change (namely sea-level rise) may have at the local level is key to contribute to effective management plans that include adaptation measures to minimize risks associated with coastal floods.

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5.
It is thought that 70% of beaches worldwide are experiencing erosion (Bird in Coastline changes: a global review, Wiley, Hoboken, 1985), and as global sea levels are rising and expected to accelerate, the management of coastal erosion is now a shared global issue. This paper aims to demonstrate a method to robustly model both the incidence of the coastal erosion hazard, the vulnerability of the population, and the exposure of coastal assets to determine coastal erosion risk, using Scotland as a case study. In Scotland, the 2017 Climate Change Risk Assessment for Scotland highlights the threat posed by coastal erosion to coastal assets and the Climate Change (Scotland) Act 2009 requires an Adaptation Programme to address the risks posed by climate change. Internationally, an understanding and adaption to coastal hazards is imperative to people, infrastructure and economies, with Scotland being no exception. This paper uses a Coastal Erosion Susceptibility Model (CESM) (Fitton et al. in Ocean Coast Manag 132:80–89. https://doi.org/10.1016/j.ocecoaman.2016.08.018 , 2016) to establish the exposure to coastal erosion of residential dwellings, roads, and rail track in Scotland. In parallel, the vulnerability of the population to coastal erosion, using a suite of indicators and Experian Mosaic Scotland geodemographic classification, is also presented. The combined exposure and vulnerability data are then used to determine coastal erosion risk in Scotland. This paper identifies that 3310 dwellings (a value of £524 m) are exposed to erosion, and the Coastal Erosion Vulnerability Index (CEVI) identifies 1273 of these are also considered to be highly vulnerable to coastal erosion, i.e. at high risk. Additionally, the CESM classified 179 km (£1.2 bn worth) of road and 13 km of rail track (£93 m to £2 bn worth) to be exposed. Identifying locations and assets that are exposed and at risk from coastal erosion is crucial for effective management and enables proactive, rather that reactive, decisions to be made at the coast. Natural hazards and climate change are set to impact most on the vulnerable in society. It is therefore imperative that we begin to plan, manage, and support both people and the environment in a manner which is socially just and sustainable. We encourage a detailed vulnerability analysis, such as the CEVI demonstrated here for Scotland, to be included within future coastal erosion risk research. This approach would support a more sustainable and long-term approach to coastal management decisions.  相似文献   

6.
Climate warming due to the enhanced greenhouse effect is expected to have a significant impact on the natural environment and human activity in high latitudes. Because of its geography, wide coastal areas, water resources, forests, and wetlands, the environment of Estonia is sensitive to climate change and sea level rise. Climate change scenarios for Estonia were generated using a Model for the Assessment of Greenhouse-gas Induced Climate Change (MAGICC) and a regional climate change database, Scenario Generator (SCENGEN). Three alternative emission scenarios were combined with data from 14 general circulation model experiments. The assessment results of forest resources using RipFor, a forest-soil-atmosphere model, show that climate warming would enhance forest growth in Estonia resulting in increased productivity (2–9%) of harvestable timber on highly productive sites. Nutrient mobility increases greatly and in highly permeable soils with stable vegetation, increased mobility may result in nutrient losses through leaching. The assessment results of water resources using the simple water balance model, WatBal, show that the runoff regime of Estonian rivers would equilibrate and the groundwater table would rise. Climate warming would not cause any particular problems with water supply but the groundwater quality may suffer from increased leaching. Due to milder winters and increased storminess, the destruction of coastal areas, inundation of wetlands and disappearance of rare plant communities in coastal areas would be the most damaging results of climate change. Most sandy beaches high in recreational value would disappear. However, isostatic uplift and settlements inland from the present coastline reduce the risk of socio-economic decline. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

7.
UNESCO promotes geoconservation through various programs intended to establish an inventory of geologically and geomorphologically significant features worldwide that can serve as an important database to understand the Earth’s global geoheritage. An ultimate goal of such projects globally is to establish geoparks that represent an integrated network of knowledge transfer opportunities, based on a specific array of geological and geomorphological sites able to graphically demonstrate how the Earth works to the general public. In these complex geoconservation and geoeducational programs, the identification of significant geological and geomorphological features is very important. These are commonly referred to as ‘geosites’ or ‘geomorphosites’, depending on whether the feature or processes the site demonstrates is more geological or geomorphological, respectively. The Kingdom of Saudi Arabia is an extraordinary place due to its arid climate and therefore perfect exposures of rock formations. The Kingdom is also home to extensive volcanic fields, named “harrats” in Arabic, referring particularly to the black, basaltic lava fields that dominate the desert landscape. Current efforts to increase awareness of the importance of these volcanic fields in the geological landscape of Arabia culminated in the first proposal to incorporate the superbly exposed volcanic features into an integrated geoconservation and geoeducation program that will hopefully lead to the development of a geopark named, “The Harrat Al Madinah Volcanic Geopark” [1]. Here we describe one of the extraordinary features of the proposed Harrat Al Madinah Volcanic Geopark, namely a steep lava spatter cone formed during a historical eruption in 1256 AD.  相似文献   

8.
The cliffed and active dune coastal region of Broome provides an excellent record of Pleistocene and Holocene stratigraphy of desert environments interfacing with the Indian Ocean. The Mesozoic Broome Sandstone is the basal stratigraphic unit in the area and is overlain by Pleistocene red desert quartz sand (Mowanjum Sand). Modern coastal processes of waves, wind and tide have resulted in distinctive sedimentary bodies (stratigraphic units) clearly linked to the sedimentary environment. The Mowanjum Sand, reworked by coastal winds, generates the landward-ingressing orange quartzose Churchill Sand, or reworked by waves and abraded to white sand with the addition of carbonate grains that form the beaches (Cable Beach Sand) and with eolian action, coastal dunes or inland-ingressing white dunes (Shoonta Hill Sand). These sedimentary bodies and stratigraphic units form a template with which to locate and interpret archaeological middens and Indigenous occupation over the past 5000?years in a context of coastal occupation, coastal stability, mean sea-level changes, climate changes, and availability of marine food and freshwater. Shell middens and stone artefacts form definitive layers or horizons in relation to the stratigraphy, in places in situ, and elsewhere reworked as sheets and plumes; understanding their inter-relationships has enabled the unravelling of the archaeological history and relating Indigenous occupation to biofacies and lithofacies. The array of sedimentary, biofacies and stratigraphic units are of national geoheritage significance in their own right. The addition of archaeological deposits as stratigraphic units provides a link between geoheritage and archaeology, where the archaeological materials are viewed as part of the complex stratigraphic story, part of the coastal history, and part of the geoheritage story.  相似文献   

9.
浙江省岛屿资源丰富,是中国海岛数量最多的一个省。海岛区各类地质遗迹资源众多,特别是海岸地貌、花岗岩地貌、地质剖面和采矿遗址等类型尤为突出,在环太平洋构造域、全新世海面变化、海岸带动力地质作用、海岸地貌景观等方面具有重要的科学研究价值和美学观赏价值,为建设海岛型地质公园提供了重要的物质基础。  相似文献   

10.
Climate change will have major impacts in the Great Lakes region of North America. Particularly vulnerable are shallow freshwater estuaries, such as Lake Michigan’s Green Bay, located in the north-eastern part of the State of Wisconsin. Green Bay and the Lower Fox River, its major tributary, were considered to be severely polluted as early as 1925. As a result of large expenditures of money and a major research effort that has been conducted over the past 40 years or more, some progress has been made toward the restoration of ecosystem integrity. However, work remains, and within this context, potential climate change impacts pose additional challenges. We discuss in this paper a methodology that can be used to assess climate change impacts on ecosystems, and describe an application to the Green Bay ecosystem. The methodology employs numerical methods to evaluate the inputs from scientific, policy, and management experts who are knowledgeable about the ecosystem under study. The Green Bay ecosystem application reveals that runoff from agriculture and urban sources, already a major ecosystem stressor, will be exacerbated in the future as a result of climate change impacts.  相似文献   

11.
《Quaternary Science Reviews》2003,22(10-13):1085-1092
Climate changes over the Holocene have directly impacted on both coastal processes and human use of coastal areas. This paper presents results from the dating of wind blown sand deposits collected from coastal and archaeological sites in Northern Scotland. Archaeological remains are frequently found interspersed with sand deposits and represent distinct periods of occupation of settlement sites within the local landscapes. In some cases storm events sufficiently inundate the sites with sand to result in periodic abandonment. Storm events can also have dramatic results on adjacent rock coastlines, with storm boulder ridges emplaced by large waves, burying sand deposits on cliff-top sites. Work has been undertaken using a quartz SAR protocol to date sand deposition at two archaeological sites in Orkney and a cliff-top site in Shetland. These dates provide chronological information, which help to construct regional chronologies of climatic instability and environmental change and allow the SAR-OSL method to be assessed as an accurate sediment dating tool in this context.  相似文献   

12.
Global warming is likely to have significant effect on the hydrological cycle. Some parts of the world may see significant reductions in precipitation or major alterations in the timing of wet and dry seasons. Climate change is one of the serious pressures facing water resources and their management over the next few years and decades. As part of the southern belt of Mediterranean Europe, Turkey is highly vulnerable to anticipated climate change impacts. The changes in global climate will seriously affect inland freshwater ecosystems and coastal lakes. Mogan and Eymir Lakes located in Central Turkey are shallow lakes that may be impacted significantly by climate change. The interaction between the lakes and groundwater system has been modelled in order to analyse the response of lake levels to climate change over a planning period of 96 years, beginning from October 2004 and ending in September 2100. The impacts of the emission scenarios of A2 and B1 of the Intergovernmental Panel on Climate Change (IPCC) on lake levels have been analyzed with the help of the lake-aquifer simulation model. The fluctuations in lake levels due to climate change scenarios are compared with the results of a scenario generated by the assumption of the continuation of the average recharge and discharge conditions observed for 1999 and 2004. The results show that very small, but long-term changes to precipitation and temperature have the potential to cause significant declines in lake levels and temporary drying of the lakes in the long-term. The impact of climate change on lake levels will depend on how these water resources are managed in the future.  相似文献   

13.
This is an overview of the geology and geoheritage of the Burren and Cliffs of Moher UNESCO Global Geopark. The geology is Carboniferous, dominated by fossiliferous Mississippian limestones and mostly coastal exposures of Pennsylvanian siliciclastics. Late Pleistocene ice sheets subsequently formed significant features in the landscape. The Cliffs of Moher is the most visited outdoor tourist attraction in Ireland and tourism is a significant income source in the Geopark area. Education and research form a key part of the Geopark programme. The Burren and Cliffs of Moher UNESCO Global Geopark is managed by Clare County Council with support from Geological Survey Ireland.  相似文献   

14.
Climate change alters global food systems, especially agriculture and fisheries—significant aspects of the livelihoods and food security of populations. The 2014 IPCC Fifth Assessment Report identified Southeast Asia as the most vulnerable coastal region in the world, and highlighted the potential distribution of impacts and risks of climate change in the region. While climate hazards may differ across geographical regions, the impact of climate extremes on food production will affect marginal farmers, fishers and poor urban consumers disproportionately, as they have limited capacities to adapt to and recover from extreme weather events. Governments and other stakeholders need to respond to climate extremes and incorporate adaptation into national development plans. Unfortunately, there is still limited peer-review publication on the subject matter. This paper presents some findings from research on observed and projected loss and damage inflicted by climate extremes on agricultural crops in Southeast Asia.  相似文献   

15.
Climate change is presently a major global challenge. As the world??s largest developing country, China is particularly vulnerable to global warming, especially in the rapidly developing coastal regions in the southeast of the country. This paper provides an overview of the impacts of climate change on the nature of geological disasters in the coastal regions of southeastern China. In the context of climate change, processes with the potential for causing geological disasters in this region, including sea-level rise, land subsidence, storm surges, and slope failures, which already have a substantial occurrence history, are all aggravated. All these processes have their own characteristics and relevance to climate change. Sea-level rise together with land subsidence reduces the function of dikes and flood prevention infrastructure in the study areas and makes the region more vulnerable to typhoons, storm surges, floods, and astronomical tidal effects. Storm surges have caused great losses in the study areas and also have contributed to increases in rainstorms. As a result, numerous rainfall-induced slope failures, characterized by focused time concentration, high frequencies, strong ??burstiness,?? and substantial damage, occur in the study areas. To prevent and mitigate such disasters that are accelerated by climate change, and to reduce losses, a series of measures is proposed that may help to achieve sustainable development in coastal southeastern China.  相似文献   

16.
A wide range of wetland types occur on the Swan Coastal Plain of Western Australia. They vary from basins, and flats, to slopes and channels, and vary in size, shape, water characteristics, sediment types, stratigraphy, vegetation, origin, and maintenance processes. The wetlands range from large linear lakes to small round or irregular seasonally damp wetland basins to seasonally flooded flats, to seasonally flooded or permanently flowing channels. Salinity ranges from fresh to saline to hyposaline; and recharge mechanisms from perching of surface-water to wetting and inundation by groundwater, as determined by regional features such as geology, geomorphology, soils, climate and hydrology, and local physical/chemical processes. The Swan Coastal Plain presents a bewildering array, diversity, and complexity of wetlands, but patterns and ordering can be recognised if the wetlands are aggregated into natural groups. The wetlands, in fact, have been aggregated into natural groupings termed ‘consanguineous suites’, resulting in some 30 different formally named wetland suites related to geomorphic setting varying, for instance, from interdune depressions on a beach-ridge plain (the Becher Suite), to karst-formed linear lakes in limestone-ridge country (the Yanchep Suite), to irregular to round, semi-interconnected basins on a quartz sand subdued dune system (the Jandakot Suite), to linear and round basins formed along the hydrological contact between limestone and quartz sand (the Bibra Suite), among others. The variety of wetland types on the Swan Coastal Plain represents geodiversity that needs to be addressed in geoheritage assessments of the State of Western Australia. Further, as repositories of Holocene to Pleistocene sedimentary sequences, the wetlands present significant reservoirs of information on wetland history, climate changes, and hydrochemical history, and are templates on wetland maintenance and functioning, diagnostic for their geologic/geomorphic setting useful for management of wetlands in Western Australia, nationally, and globally. From a global perspective, the diversity and array of consanguineous suites of the Swan Coastal Plain is unique. An understated aspect of the approach in identifying consanguineous suites of wetlands of the Swan Coastal Plain is that in their geological, geomorphological, and hydrological/hydrochemical setting they provide profound insights into gradual and uninterrupted wetland development, sedimentary filling and ecological functioning because, for a given east–west transect, they are located in the same climate setting but in different geologic/geomorphic and hydrochemical settings. They appear to be unrepresented globally, and therefore, in terms of geoheritage, are internationally significant.  相似文献   

17.
This report chooses Clarence City Council as the coastal jurisdiction and analyzes its planning processes and instruments for its potential to build resilience to climate change impacts on the coast. In the first part, it introduces the change of Australia’s climate and consequences of climate change. Based on analysis of sea level rise, inundation and erosion risk, it shows climate change has impacts on Clarence coastal areas in Tasmania. This paper shows the three key elements for successful coastal management (retreat, accommodation and protection) and discusses the factors that impede resilience. Finally, there are some recommendations that may be helpful for climate change impacts and local council  相似文献   

18.
我国冰冻圈变化的影响在气候变化背景下的识别   总被引：1，自引：1，他引：0  
全球气候变化对自然生态系统和人类社会系统的各个方面产生了很重要的直接影响,其中冰冻圈由于其脆弱性与灵敏性而首当其冲.同样,气候变化通过影响冰冻罔而对自然生态系统和人类社会系统产生很重要的间接影响.通过论述冰冻圈变化的影响,选取较为典型的领域,在时空尺度、作用机制以及影响过程等方面,对气候变化背景下我国冰冻圈变化的具体影响进行了识别.结果表明,气候变化的正面或者负面影响通过冰冻圈变化的作用之后可以加强或者削弱,从而为制定冰冻圈变化的适应对策提供科学依据.  相似文献   

19.
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20.
Vu  M. T.  Raghavan  V. S.  Liong  S.-Y. 《Natural Hazards》2017,85(3):1877-1891
Natural Hazards - Climate change is expected to exacerbate the extremes in the climate variables. Being prone to harsh climate impacts, it is very crucial to study extreme rainfall-induced flooding...  相似文献   

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